Apparatus for supplying powdered fuel to furnaces



March 11, 1930. E. HERIWSDORF APPARATUS FOR SUPPLYING POWDERED FUEL TO FURNACES Filed Oct. 3. 192a ,Ewaldflcrmsdoifl Patented Mar. 11, 1930 UNITED STATES PATENT OFFICE APPARATUS FOR SUPPLYING POWDERED FUEL TO FURNACES Application filed October 3, 1928, Serial No.

My invention relates to improvements in apparatus for supplying powdered fuel to funaces, and more particularly in apparatus in which the powdered -fuel is carried to the furnace by ablast of air. The object of the improvements is' to provide an apparatus in which the mixture of powdered fuel and air is supplied to the furnace at low pressure. With this object in View my invention con sists in providing one or more pipes for supplyin air at low pressure below the intake endo thepassage for supplying the fuel, and so that the whole amount of air is delivered from the said pipe or pipes into the said passage in a closed current and without being distributed, and that always only a comparatively thin layer of powdered fuel is located in front of the said pipes.

For the purpose of explaining the invention an example embodying the same has been shown in the accompanying drawing in which the same letters of reference have been used in all the views to indicate correspond ing parts.

In said drawing,

Fig. 1, is a sectional elevation showing the bottom part of the container for the powdered fuel, the conduit for conveying the fuel from the container to the furnace and the pipes for'blowing the fuel into said conduit, and

Fig. 2, is a detail view showing the said pipes.

In the example shown in the drawingthe apparatus comprises a container a having a tapering bottom part and adapted to receive the powdered fuel. Within the container (1 there is a concentric conduit 6 having an outwardly flaring bottom end and ending near the bottom of the container a. Below the intake end of the conduit 6 there are four substantially horizontal pipes a connected with a common pipe at supplied from any suitable source with air under low pressure, and the delivery ends of the pipes 0 are directed upwardly and into the conduit 12. Preferably the inclination of the delivery ends of the pipes c is such that the ends of the pipes 0 are substantially parallel to the slope of the powdered coal located below the conduit 12. A part of the powdered fuel 310,053, and in Germany September 7, 1927.

flowing to the pipes c by gravity is blown by the blast of air from the pipes 0 into the conduit b and carried therethrough to the place of use. Preferably the container (1 is provided with an elastic bottom e, and suitable 1arring means are provided for shaking the said elastic bottom from below. As shown, the said jarring means is in the form of a hammer g pivoted at f and acted upon by a spring h, a rotary finger i being provided for alternately forcing the hammer 9 downwardly against the tension of spring k and releasing the same, so that the hammer g is thrown against the bottom e by the said spring it. Thus the powdered fuel is thrown upwardly by the bottom 6 and into position for being acted upon by the blast of air rushmg from the pipes a. In order to cause the powdered fuel to move downwardly and towards the pipes c, an agitating ring is is rovided, which is connected with the elastic ottom 6 and takes part in the vibration thereof, the said ring being located within the body of powdered fuel, thus transmitting the vibration of the bottom to the powdered fuel, whereby the fuel is stirred up and caused to flow continually.

The amount of' dust taken by the blast from the container a can be regulated by vary ng the supply of air to the pipes a, or by varying the distance between the bottom end of the conduit 6 and the delivery ends of the pipes a, so that a greater or smaller amount of fuel is supplied to the blast of air.

I claim:

1. An apparatus for deliverin finely di vided material such as powdered fuel comprising a container, a conduit having an intake in the container, means for supplyin airunder low pressure directly below said intake including a port underneath the intake with its marginal edges in an inclined plane corresponding approximately 'to the angle of repose of the material being delivered, said port being far enough from the margin of said intake to permit only a thin layer of such material to flow across said port.

2. An apparatus for delivering finely divlded material such as. powdered fuel comprising a container, a conduit having aninsaid open lower end and said air supplying take in the container, means for supplying m air under low pressure directly below said eans, and means for jarringthe r1ng.- In testimony whereof I have afiix'ed my intake including a circular series of ports 5 underneath the intake s aced inwardly from the margin of the inta e, said ports lying approximately in planes corresponding to the angle pf repose of said material.

3. An apparatus for delivering finely die vided material such as powered fuel c0m-.

, prising a container, a conduit having an intake in the contamer, means for supplying signature.

air under low pressure directly below said intake including a circular series of ports underneath the intake each having its marginal edges in an inclined plane corresponding approximately to the angle of repose of said material and each being near enough to permit only a thin layer of said material to go flow by gravity across said ports.

4. An apparatus for feeding powdered fuel, comprising a container, a conduit within said container with an intake at its lower end, and a plurality of pipes disposed 5 circularly of said conduit to which pi es air is supplled under low pressure, sa1 pipes having openings each delivering a current of air directly into the said intake and the plane of each opening corresponding approximately to the angle of repose of the powdered fuel.

5. An apparatus for feeding owdered fuel, comprising a container, a con uit within said container, a pipe to which air is supplied under low pressure said pipe having an opening delivering a current of air directly into the said conduit, the relative positions of the intake end of the said conduit and the delivery opening of the said pipe being such that only a thin layer of powdered fuel can gather in front of the pipe, an elastic bottom for said container, and jarring means for vibrating said elastic bottom.

6. An apparatus for feeding powdered fuel, comprising a container, a conduit within said container, a pipe to which air is supplied under low pressure having an outlet opening for delivering a current of air directly into the said conduit, the relative posim tions of the intake end of the said conduit and the delivery end of the said pipe being such that only a thin layer of powdered fuel can accumulate in front of the pipe, an elastic bottom for said container, jarring means for vibrating said elastic bottom, and an agitating member carried by said elastic bottom said agitating member being located within said container.

7. An apparatus for feeding finely divided c material such as powdered fuel comprising a container, a conduit extending upwardly in the container said conduit being open at its lower end, means directlybelow such open lower end for supplying air at low pressure 05 to the conduit, an agitating ring encircling EWALD HERMSDORF. 

